No, it's not. You know, I'm having trouble not coming to the conclusion that you're an idiot. If you had a clip that could be used in any type of weapon it would still have to be fed into the weapon. Seriously, it's not that big a deal, but just drop it, it doesn't make any sense
Maybe it would help if you would stop assuming you're right and think about what you're asking.
Last try to explain this. Load the demo. Go to the room with the shotgun and ammo. Take both. Arm the shotgun. Fire enough rounds that the ammo bar is almost depleted. Switch to pistol. Fire like, two shots and the "clip" is gone.
If you had your wish, you would have just reloaded. Is that more realistic? No, because you weren't firing the pistol before. It doesn't increase immersion or plausibility, it reminds players of the unified ammo system and how little sense it makes.
Does it make it more strategic? No. In fact, it punishes you for doing something common in a reload system - swapping to a fully loaded weapon instead of taking the time to reload the current one. Now you have to reload any weapon.
It would add annoyance and nothing more. Well, some more weapon animations.
The only real solution is different weapons having different clips and different ammo levels. At that point you would pretty much have different ammo types and no unified ammo system. Well, you could just have some animations but that would just be lip service.
It's the exact same system as Jedi Knight with a different HUD setup. Does that make it OK? Not really, unless they made all the weapons energy based. But reloading is still a victim of the unified ammo, whether you like it or not.
At this point, if you don't buy it, go to the ion storm forums and ask them. You've descended into name calling over this and I don't have any more desire to debate with someone being an asshole over a game discussion - so take it to them. But I'll bet dollars to donuts that reloading and the ammo decisions were married to each other.